Avoiding patent infringement.

James Pickard modified the Newcomen steam engine to deliver rotary motion using a crank (and patented it). So James Watt used the sun and planet for his steam engine to avoid infringing the patent.

The Picard patent specifies that the crank is fixed to the driveshaft, but it is free to rotate in the sun and planet setup

Looks like there's contact between the outer diameter of the sun-gear and a surface close to the center of the planet-gear? The link arm is pulling them together and this contact keeps them apart I guess. The rotation speeds are different so you'd need a bearing? I dunno tbh - I'm not sure what the colors represent and I'm not even sure if I'm using the correct words to describe what I see.